From: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
To: Arnd Bergmann <arnd@arndb.de>
Cc: kosaki.motohiro@jp.fujitsu.com, Tejun Heo <tj@kernel.org>,
linux-kernel@vger.kernel.org
Subject: Re: lockdep warning: events vs. bd_mutex
Date: Tue, 14 Sep 2010 16:27:44 +0900 (JST) [thread overview]
Message-ID: <20100914160729.C9A1.A69D9226@jp.fujitsu.com> (raw)
In-Reply-To: <201009122243.23765.arnd@arndb.de>
> [ 464.602109] -> #3 (&bdev->bd_mutex){+.+.+.}:
> [ 464.602109] [<ffffffff8106dad4>] lock_acquire+0xe3/0x110
> [ 464.602109] [<ffffffff813f5b5b>] __mutex_lock_common+0x4b/0x35e
> [ 464.602109] [<ffffffff813f5f32>] mutex_lock_nested+0x3e/0x43
> [ 464.602109] [<ffffffff8111d7df>] revalidate_disk+0x4b/0x73 // grab bd_mutex
> [ 464.602109] [<ffffffff812a969f>] sd_rescan+0x27/0x34
> [ 464.602109] [<ffffffff812a1be6>] scsi_rescan_device+0x82/0x98
> [ 464.602109] [<ffffffff812b53e5>] ata_scsi_dev_rescan+0x8d/0xf4 // on system_wq
> [ 464.602109] [<ffffffff810558b0>] process_one_work+0x232/0x399
> [ 464.602109] [<ffffffff8105759a>] worker_thread+0x13b/0x251
> [ 464.602109] [<ffffffff8105ace8>] kthread+0x82/0x8a
> [ 464.602109] [<ffffffff81003a64>] kernel_thread_helper+0x4/0x10
ata_scsi_dev_rescan() was invoked by schedule_work() from ata_eh_revalidate_and_attach().
IOW, it use system_wq.
> [ 464.602109] -> #0 (events){+.+.+.}:
> [ 464.602109] [<ffffffff8106d6e9>] __lock_acquire+0xa30/0xd38
> [ 464.602109] [<ffffffff8106dad4>] lock_acquire+0xe3/0x110
> [ 464.602109] [<ffffffff810567e7>] flush_work+0xfc/0x143 // wait system_wq
> [ 464.602109] [<ffffffff81056903>] schedule_on_each_cpu+0xd5/0x115
> [ 464.602109] [<ffffffff810c6f06>] lru_add_drain_all+0x15/0x17
> [ 464.602109] [<ffffffff81118b93>] invalidate_bdev+0x2d/0x3f
> [ 464.602109] [<ffffffff8111d16c>] __invalidate_device+0x48/0x53
> [ 464.602109] [<ffffffff811ebf1d>] invalidate_partition+0x2d/0x42
> [ 464.602109] [<ffffffff8114ac31>] rescan_partitions+0x63/0x40e
> [ 464.602109] [<ffffffff8111e2f0>] __blkdev_get+0x269/0x32f // grab bd_mutex
> [ 464.602109] [<ffffffff8111e3c6>] blkdev_get+0x10/0x12
> [ 464.602109] [<ffffffff8114a35d>] register_disk+0xdc/0x13f
> [ 464.602109] [<ffffffff811eb5f0>] add_disk+0xaf/0x10b
> [ 464.602109] [<ffffffff812abd2b>] sd_probe_async+0x129/0x1cd
> [ 464.602109] [<ffffffff81061847>] async_run_entry_fn+0xa8/0x15b
> [ 464.602109] [<ffffffff810558b0>] process_one_work+0x232/0x399
> [ 464.602109] [<ffffffff8105759a>] worker_thread+0x13b/0x251
> [ 464.602109] [<ffffffff8105ace8>] kthread+0x82/0x8a
> [ 464.602109] [<ffffffff81003a64>] kernel_thread_helper+0x4/0x10
lru_add_drain_all() wait system_wq.
Probably we have four choice.
1) simple revert buggy patch (I don't know how much serious original issue)
2) ata_scsi_dev_rescan() doesn't use system_wq
3) lru_add_drain_all() doesn't use system_wq
4) make IPI version lru_add_drain_all()
I'd like to hear Tejun's opinion.
next prev parent reply other threads:[~2010-09-14 7:27 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-12 20:43 Arnd Bergmann
2010-09-14 7:27 ` KOSAKI Motohiro [this message]
2010-09-14 7:49 ` Tejun Heo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20100914160729.C9A1.A69D9226@jp.fujitsu.com \
--to=kosaki.motohiro@jp.fujitsu.com \
--cc=arnd@arndb.de \
--cc=linux-kernel@vger.kernel.org \
--cc=tj@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®